School administrator found dismembered, suspect arrested

A suspect has been arrested after a teenager found the dismembered body parts of a school security guard.

Investigators in Bay City, Michigan, responded to reports of human remains found near a boat launch on Wednesday, Sept. 18, the Bay City Department of Public Safety said in a statement. The following day, authorities identified the victim as 41-year-old Justie Stilwell of Bay City.

On Wednesday, Sept. 25, Bay City Public Safety officers arrested a 40-year-old man in connection with the discovery, a statement said. Authorities did not release the suspect's name, but he was identified as Robert Tweedly Jr. by WNEM, MLive and the Midland Daily News after his arraignment Friday in a Bay City court, where he was charged with one count of open murder and one count of digging up and mutilating a corpse in connection with Stilwell's death.

Public safety officials in Bay City say Stilwell's family reported him missing on Sept. 18, just hours before his remains – two arms and lower legs, including his feet – were found near a boat dock on the banks of the Saginaw River .

The discovery was reportedly made by a 16-year-old girl who was walking past the boat dock, spotted a foot in the water and notified her grandfather, Bay City Deputy Director of Public Safety Rod Schanck said, according to MLive.

The girl's grandfather, John Donaldson, said he initially thought it was a Halloween prank and that the foot looked like it belonged to a doll, according to the outlet.

After realizing it was a human foot, Donaldson called 911, and while the two waited for police, the teen also reportedly spotted a hand, Donaldson said, according to MLive.

The next day, Stilwell's car was found by his family in a nearby park, Bay City public safety officials said.

On Wednesday, the same day Tweedly was arrested, authorities also allegedly found “additional human remains” believed to be those of Stilwell at another, undisclosed location in the city, a statement said Explanation.

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After identifying the victim, TL Handy Middle School, where Stilwell worked, issued a statement, according to MLive The Detroit Free Press.

“Justie was a valued member of our Handy family and we know this loss will be deeply felt by many,” part of the statement read. “Our thoughts are with Justie’s family and everyone affected by this loss.”

The suspect has pleaded not guilty to both charges against him Midland Daily News and radio station WSGW. According to media reports, he is being held on $1 million bail. PEOPLE was unable to find an attorney for him.